Similar to the Cold Steel Pocket Bushman...that one doesn't have a stop pin though. I'm not sure, but it might also be similar to the D.O.G (Deadbolt over grabstep) lock.
~Chip
I have thought of a very similar locking mechanism. I don't see why it wouldn't work. I think it would be self adjusting for imperfections because of the wedge shape that fits underneath the stop pin.
With the location of that stop pin, it does not look like it will close... Unless I am missing something?